As the technique for removing the high-dose ion implantation resist on the substrate, for example, they have been disclosed in the following Patent Documents.
In Patent Document 1, a method for plasma processing and its apparatus have a substrate bias application means and a substrate heat application means, and the plasma processing is performed to the substrate using a helicon wave plasma processing. More specifically, a resist mask on the substrate is removed by an ion mode-dominated plasma processing that utilizes a high ion current by the helicon wave plasma and a radical mode-dominated plasma processing by a non-resonant inductively coupled plasma.
In Patent Document 2, a method for plasma processing and its apparatus have a transparent bell jar made of dielectric material that allows UV rays to pass through, and ashing of a hardening affected layer of a resist mask on a substrate is performed by the plasma processing apparatus. Further, by application of the UV rays in an ozone atmosphere, asking of an unaffected layer of the resist mask on the substrate is performed.
In Patent Document 3, a resist removal method and its apparatus heat a substrate and intentionally induce a popping phenomenon in a resist on a surface of a substrate. The resist is then peeled off by an adhesive tape after cooling the substrate. Subsequently, ashing is performed with oxygen plasma, ozone (see Patent Document 4) or a combination between UV and ozone.
Regarding the high-dose ion implantation resist, a filmy hardened layer is formed on the surface of the substrate. Since a lower layer of this resist is a soft resist (the unaffected layer), when heating the substrate, e.g. when heating the substrate up to a high temperature more than 200° C., the so-called popping phenomenon, in which the surface cracks due to outgassing from the unaffected layer of the lower layer and/or thermal expansion difference then blows off, occurs. The popping phenomenon pollutes not only the substrate but also an inside of a chamber in which the substrate is set with the blowing-off hardened layer of the substrate surface.
Therefore, the resist removal method including such heating process as described in Patent Document 3 reduces the yield of the device which can be obtained from the substrate. Furthermore, a maintenance cycle of the manufacturing apparatus must be shortened, and these affect a throughput of the substrate.
On the other hand, in such processing method as described in Patent Document 1, Patent Document 2 and Patent Document 4, although the popping phenomenon can be suppressed, a plasma generator is required for the apparatus and the method. The plasma generator is expensive. In addition, if this plasma generator is added, system of the apparatus for removing the resist becomes great. Moreover, an energy cost for resist removal rises.    Patent Document 1: Japanese Patent Application Publication No. JP8-69896 (paragraphs [0010]˜[0016])    Patent Document 2: Japanese Patent Application Publication No. JP8-139004 (paragraphs [0011]˜[0023])    Patent Document 3: Japanese Patent Application Publication No. JP9-27473 (paragraphs [0008]˜[0011])    Patent Document 4: Japanese Patent Application Publication No. JP2006-294842 (paragraphs [0016], [0026])